A nurse is assessing a client who has been experiencing frequent infections. Which laboratory value would be most important for the nurse to monitor to evaluate the client's immune response?
1Hemoglobin level
2Blood glucose level
3Serum albumin level
4White blood cell count✓ 정답
해설
White blood cell count is most important for evaluating immune response as WBCs are primary cells fighting infections. Other options (hemoglobin, glucose, albumin) assess different functions like oxygen transport, diabetes, or nutrition, not direct immune function.
When a client presents with recurrent infections, the priority is to evaluate the body’s primary defense mechanism against pathogens. The immune response is largely mediated by leukocytes, which are measured as the white blood cell (WBC) count. Monitoring this value provides direct insight into the bone marrow's ability to produce immune cells and the body's capacity to fight infection.
The provided case report on secondary dengue infection underscores the critical role of WBC kinetics in clinical management [1]. Dengue, a viral illness, often leads to significant leukopenia (a decrease in WBCs), which increases susceptibility to secondary infections. The study highlights how monitoring the "dynamic changes observed in extended white blood cell differential count" is essential for evaluating disease progression and immune status [1]. This principle applies broadly: a low WBC count (leukopenia) can explain why a client is experiencing frequent infections, as their body lacks sufficient circulating immune cells. Conversely, a high WBC count (leukocytosis) often signals an active bacterial infection, representing the immune system's response. Therefore, the total WBC count with differential is the most direct and relevant indicator of immune function among the options listed.
The other laboratory values, while important in a general assessment, do not directly measure the cellular immune response in the same way. Hemoglobin reflects oxygen-carrying capacity, not leukocyte activity. Blood glucose levels, particularly when elevated, can impair immune cell function over time, but a single measurement does not provide a direct snapshot of the current immune response. Serum albumin is a marker of nutritional status and chronic inflammation; although severe malnutrition (hypoalbuminemia) can depress immunity, it is an indirect and less specific indicator compared to the direct count of immune cells. The case report’s focus on the kinetics of the WBC and inflammatory markers confirms that for evaluating the immediate immune response and risk of infection, the white blood cell count is the most important and actionable laboratory value to monitor [1].
References (research sources)
[1]
Rethinking the Kinetics of Extended WBC Differential Count and Inflammatory Index Marker in Secondary Dengue Infection: Case Report at University Hospital.Case reportSugianli AK, Aulia N, Sari YANA, Hamdan AR, Fauziah N, Logito V. (2026) · DOI: 10.2147/imcrj.s594518
Clinical Guide: Evaluating Immune Response in Recurrent Infections
When a client presents with frequent infections, the white blood cell (WBC) count with differential is the cornerstone laboratory test for evaluating immune competence. This test provides direct insight into the bone marrow's production of leukocytes and the body's primary defense against pathogens.
Key Clinical Actions
Order a CBC with differential as the initial diagnostic step to quantify total WBCs and identify specific cell line abnormalities (neutrophils, lymphocytes, monocytes).
Interpret WBC trends rather than a single value. A downward trend (leukopenia) may indicate bone marrow suppression or viral infection, while an upward trend (leukocytosis) often signals bacterial infection or inflammation.
Correlate with clinical presentation. Fever with leukocytosis suggests bacterial etiology; fever with leukopenia may indicate viral illness or sepsis in immunocompromised patients.
Implement infection prevention precautions for patients with severe neutropenia (absolute neutrophil count less than 500 cells/mcL), including protective isolation and strict hand hygiene.
Nursing Considerations
Monitor vital signs and assess for subtle signs of infection, as immunocompromised patients may not mount a typical febrile response.
Educate patients on signs of infection (fever, chills, localized redness or swelling) and when to seek immediate medical attention.
Coordinate with the healthcare team to investigate underlying causes of recurrent infections, such as immunodeficiency disorders, medications, or chronic diseases.
While hemoglobin, glucose, and albumin provide valuable information about oxygenation, metabolism, and nutrition respectively, they do not directly measure the cellular immune response and should be considered complementary assessments.
White Blood Cell (WBC) Count — A laboratory test measuring the total number of leukocytes in a blood sample, serving as a primary indicator of immune function and the body's capacity to fight infection.
Leukopenia — A decrease in the total white blood cell count, which increases susceptibility to infections and may explain recurrent infectious episodes.
Leukocytosis — An elevated white blood cell count, often signaling an active bacterial infection and representing the immune system's response to pathogens.